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September 9, 2010, 2:50 am
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    Posts Tagged ‘great white sharks’

    Whether you think of Great White Sharks as ferocious or just misunderstood, you have to admit they are exciting animals. Due to their nomadic lifestyle and periodic deep water forays, we have limited knowledge about them, which perhaps adds to their mystique. We do know that these powerful sea-dwellers can grow to over 20 feet and live to upwards of 100 years. They are found in almost all coastal and offshore waters which have water temperature between 54 and 75 °F, with greater concentrations off the coasts of Australia, South Africa, California, the northeastern US, Mexico’s Isla Guadalupe, New Zealand and the waters of the Mediterranean. Their preferred habitat is the cooler, deeper waters of the ocean and the waters around oceanic islands and rocky outcrops where deep water is within easy reach.

    Great Whites are truly apex predators. They are capable of sensing the blood of an injured animal from over a kilometer away. Their Ampullae of Lorenzini organ, which enables them to detect and stalk the electromagnetic field emitted by the movement of living animals, can detect movement that generates as little as half a billionth of a volt. Though Hollywood has spectacularly portrayed them as preferring humans for lunch, they actually live on a diet of fatty fish and animals such as rays, tuna, smaller sharks, dolphins, porpoises, whale carcasses, seals, sea lions, and occasionally sea birds. Diving with Great White Sharks is certain to be on anyone’s list of Most Extreme Scuba. So, where can aquanauts meet these beauties eye to eye?

    • Farallon Islands, California, USA – The Farrallones are located 28 miles west of San Francisco. A protected National State Wildlife Refuge since 1969, the Farrallones are an important research spot for great whites. These islands are one of the few places in the world where great whites can be observed in predatory attacks upon seals, birds, and sea lions from dry land. But doesn’t getting in the water with them sound like such a better idea? Cage diving is offered from late-September through November. Divers are offered a tank/regulator or a hookah setup. Since random chumming of the water is illegal in the Refuge, operators often pull along seal “decoys” to attract the sharks. It is an amazing day trip from the city, with many of the operators leaving right from the tourist hub of Fisherman’s Warf.

    • Isla de Guadalupe, Pacific Coast, Mexico – Guadalupe Island is a volcanic island about 145 miles offshore of Baja Mexico, 200 miles south of San Diego. Due to the remote location of the island, this trip is done via a live aboard operation over multiple days. The island has a dramatic sheer rock wall extending hundreds of feet up into the air, as well as hundreds of feet into the ocean. The islands’ large population of seals attracts the white sharks in large numbers. The rocky outcrops of the islands have dramatic drop-offs around the edges that reach down into cool, deep water, also attracting our toothy friends. Visibility at this site is fantastic, up to 100 feet or more. Also, the water temperature ranges from 67 to 70 F, making it much warmer than some other Great White watching spots.

    • Dyer Island, False Bay, South Africa – South African Great White cage diving occurs mainly in False Bay and the Whale Coast. Dyer Island is a small, low, and rocky island located just offshore from Gansbaai in the Western Cape of South Africa. During winter, the warm Agulhas Current sweeps down from the Indian Ocean, meeting the cold Benguela Current, creating a temperate zone just off the South African coast – providing ideal conditions for the Great White Shark in particular. This island serves as a breeding ground for a wide variety of seabirds, while its neighbor, Geyser Rock, serves as a home for a large resident seal population. White Sharks are seen on a regular basis in the channel between the two islands (“Shark Alley”) where they feed on a variety of seals, seabirds, and penguins. As an added bonus, Great White sharks in these waters often display very unusual, but highly spectacular breaching when chasing their prey, which makes for some amazing topside photos.

    • The Neptune Islands, South Australia – The Neptune Islands sit on a shelf south east of Port Lincoln off South Australia. Grey granite and coastal loam make up these picturesque islands, which support an array of wildlife, including many bird species, a large colony of fur seals, as well as a colony of endangered Australian sea lions. Known as the place where the hit movie “Jaws” was filmed, the waters around these islands are a natural feeding area for Great Whites. Most shark diving here is done via a live aboard vessel. Operators practice cage diving combined with surface bait to give divers an unforgettable experience, sometimes with more than one Great White in sight at a time. The water is very cold here, but the shark action is definitely hot.

    • Lampedusa, Sicily, Italy –Have you swam off the coast of Sicily or found the offshore waters of Nice to be nice? Oh yes, there were Great White sharks there, and you didn’t even know it. Great White sightings are becoming more common in the Mediterranean, where a high concentration of nutrients attracts some of the whites’ favourite snacks: large pelagic fish, dolphins and turtles. There have been numerous sightings of the Whites along the Spanish, French, Italian and Croatian coasts, but by far the largest concentration of the sharks is in the channel between Sicily and Tunisia. As far as I can determine, no one does cage diving here because of the infrequent nature of the sightings. However, there are many dive companies that operate out of Lampedusa, Sicily, which puts you in waters with the highest density of Great White sightings in all of the Mediterranean. Divers have encountered large white sharks while diving in the open sea at Sicilian Channel sites such as Pantelleria, Malta, and southwest Marretimo. Though rare, these experiences are as amazing as you can get: no chumming, no decoys and no cage bars between you and the jaws of the Great White.

    Vinnie the Venomous Fish

    Vinnie the Venomous Fish

    Great White sharks get all the press when it comes to discussion of the ocean’s deadliest killers.  But, plenty of other things in the sea are just as mean and nasty, if not more so.  A selection of some of my favorites:

    Vinnie the Venomous Fish – Imagine being a lowly fish, armed only with the ability to school and a sense of sea humor.  Now add a little venom to your arsenal, and suddenly you are a Big Bad Swimming Machine.  Venomous fish like stonefish, lionfish and scorpion fish produce their own toxins then generously share it with the rest of the aquatic world via their already unpleasant spines.  My favorite is the stonefish, who are at their deadliest when lying on the ocean bottom doing nothing at all except looking like…you guessed it…an ugly stone.  All it takes is a passerby with a naked foot and a bad aim and bam, you get one unhappy tourist (and the fish is a little flatter for the experience as well.)

    Octopussy – James Bond proved one could overcome their enemies by throwing a Blue Ringed Octopus on their face in this classic 1980’s spy movie.  Theoretically I suppose this could work, though you are likely to get bitten in the process.  Since it injects neuromuscular paralyzing venom that can kill a human in minutes, you won’t really get to enjoy your victory over the forces of evil for very long.  Better to remove the bad guy’s shoes and point him in the direction of some stonefish instead.

    They Freak Me Out On Land, Too – Sea snakes tend to favor the warm, fish-filled tropical waters that most scuba divers also like.  Though shy unless provoked, a single snake produces enough poison to kill not only you, but the rest of the folks on your dive boat, too.  Most are a normal snake size, but a few can grow to seven feet or more.  I personally am sure that if I ran into a seven-foot sea snake while diving I would give up the sport right then and there.

    Vinnie the Venomous Fish

    Vinnie the Venomous Fish

    Great White sharks get all the press when it comes to discussion of the ocean’s deadliest killers.  But, plenty of other things in the sea are just as mean and nasty, if not more so.  A selection of some of my favorites:

    Vinnie the Venomous Fish – Imagine being a lowly fish, armed only with the ability to school and a sense of sea humor.  Now add a little venom to your arsenal, and suddenly you are a Big Bad Swimming Machine.  Venomous fish like stonefish, lionfish and scorpion fish produce their own toxins then generously share it with the rest of the aquatic world via their already unpleasant spines.  My favorite is the stonefish, who are at their deadliest when lying on the ocean bottom doing nothing at all except looking like…you guessed it…an ugly stone.  All it takes is a passerby with a naked foot and a bad aim and bam, you get one unhappy tourist (and the fish is a little flatter for the experience as well.)

    Octopussy – James Bond proved one could overcome their enemies by throwing a Blue Ringed Octopus on their face in this classic 1980’s spy movie.  Theoretically I suppose this could work, though you are likely to get bitten in the process.  Since it injects neuromuscular paralyzing venom that can kill a human in minutes, you won’t really get to enjoy your victory over the forces of evil for very long.  Better to remove the bad guy’s shoes and point him in the direction of some stonefish instead.

    They Freak Me Out On Land, Too – Sea snakes tend to favor the warm, fish-filled tropical waters that most scuba divers also like.  Though shy unless provoked, a single snake produces enough poison to kill not only you, but the rest of the folks on your dive boat, too.  Most are a normal snake size, but a few can grow to seven feet or more.  I personally am sure that if I ran into a seven-foot sea snake while diving I would give up the sport right then and there.

    This is not a Great White, but he plays one on TV...

    This is not a Great White, but he plays one on TV...

    Great White sharks have invaded Cape Cod, Massachusetts.  Only yesterday two were tagged, with at least three more sighted.  This marks an interesting point in history, not only for the beach-goers who have to stay out of the water all weekend long, but also for the Massachusetts Division of Marine Fisheries which can now claim the first successful tagging of a Great White shark in the Atlantic Ocean.  What I want to know is this:  Why were the sharks on Cape Cod to begin with?  A few (potentially) compelling reasons:

    1. Moving further up North made sense since staying too long in the waters off New Jersey causes them to glow in the dark.  Not so subtle for a stalker.
    2. You can get lobster rolls without the shells at the Cape.
    3. Better dental plans in Massachusetts.
    4. “Hey Phil, I told you we should have kept going straight when we passed Johannesburg!”

    high res mantaWhen I heard that Hurricane Jimena, currently a category 4 storm and the tenth storm of the season in the Pacific, was barreling down on Baja California, I thought I hope it won’t hurt the scuba diving there. Then I realized I had no clue what kind of diving was there. After a little research I now hope more than ever that Jimena decides she wants an authentic tamale and veers significantly to the right into a low-population area.

    The Baja peninsula actually has an amazing array of diving opportunities, from the rocky kelp forests in the north on the Pacific coast near San Diego to the only live coral reef on the western side of North America, Cabo Pulmo, on the Sea of Cortez between La Paz and Cabo San Lucas. The indigenous sea life is insane, including great white sharks, hammerhead sharks, tiger sharks, whale sharks, manta rays, dolphins, marlin, Humboldt squid, octopus, and whales. In some spots divers encounter sea lions frequently eager to play or gnaw the end of your fin.

    I can’t wait to book my next trip: the Baja Peninsula has moved up to #1 on my “to dive” list. I’ll just wait until Jimena checks out of the hotel.